Turbulent winds and pressure effects around a rough cylinder at high Reynolds number

Abstract

Time histories of the fluctuating wind pressure differential across the shell of a full-scale cooling tower were measured in 1974 by Princeton University personnel. Data were recorded around a single level, at the throat, at a height of ∼100 m. A set of simultaneous three-minute records from these data is examined statistically in the present paper. The methods employed include spectral and correlation analyses, plus parametric time-series characterization of the data. Aside from its direct engineering interest as an aid in defining dynamic wind-loading conditions, the fluctuating flow activity around the tower throat may be interpreted as a fair example of turbulent flow about a rough circular cylinder at a Reynolds number approaching 10 8. This aspect is emphasized in the present paper. In this situation the relation of the spectrum of the incident wind to pressure spectra about the cylindrical section may be of interest in connection with theories of the deformation of turbulence by bluff bodies. Further, the spatial distribution of the “parsimonious” parameters obtained from an autoregressive time-series analysis of the data reveals strong correlations with clearly identifiable flow phenomena around the perimeter, such as key points of the pressure distribution, flow separation, etc. The study, although limited to a single wind record, sixteen peripherally spaced pressure records, and only three minutes of selected time-history data, develops a coherent picture of a turbulent flow phenomenon at high Reynolds number.